LIGO AIR Datasheet

Product Overview

LIGO AIR is a wireless fuel level sensor developed and manufactured by SOJI Electronics JSC. The device is designed to measure the level of liquid fuel and other non-conductive liquids in vehicle tanks and stationary fuel storage applications.

The sensor uses capacitive measurement technology combined with Bluetooth Low Energy 5.4 wireless transmission, eliminating the need for complex wiring and reducing the risk of signal wire tampering. The heavy-duty metal housing meets the IP69K ingress protection standard, providing reliable operation against dust, moisture, vibration, and high-pressure high-temperature water cleaning typical in industrial environments.

LIGO AIR maintains stability, durability, and operational lifespan equal to or greater than traditional wired sensors, with battery life ranging from 6 to 12 years depending on variant selected.

File:LIGO-AIR-product-overview.png

LIGO AIR Wireless Fuel Level Sensor

Key Features

• Wireless: Bluetooth Low Energy 5.4 with directional antenna — 1.5× range compared to typical market sensors
• Ultra-low power consumption: 9 µA working mode, 4 µA storage mode
• Long battery life: 8–10 years standard, 8–12 years extended variant
• High accuracy: up to 99.5% measurement accuracy (± 0.5%)
• Wide operating temperature: -40°C to +85°C
• Long-range TX power: up to 19.5 dBm (LIGO AIR PRO variant)
• High capacity battery: up to 3600 mAh (PRO variant), replaceable
• Built-in 32 Mb EEPROM for data logging (90 days) and setting logs (max 500)
• IP69K ingress protection — survives dust, water jets, high-pressure cleaning
• Customizable length: 700 mm to 6000 mm
• Built-in accelerometer (LIGO AIR PRO)
• Multi-protocol support: SOJI, Mielta, Escort — configurable via mobile app
• Anti-mud oil filter and anti-vibration springs included
• Anti-tampering design — wireless eliminates wire cutting fraud risk

Applications

• Heavy-duty trucks — long-haul transport, cargo vehicles
• Construction machinery — excavators, cement mixers, bulldozers
• Marine vessels — ships, fishing boats, offshore platforms
• Power generation — diesel generators, backup power systems
• Industrial fuel storage — stationary tanks, distribution depots
• Off-highway equipment — mining vehicles, agricultural machinery
• Fleet management — telematics-integrated fuel monitoring

Product Variants / Ordering Information

Product Variants

The LIGO AIR series offers three variants optimized for different operational priorities:

Variant	Description	Battery Life	Transmission Range	Best For
LIGO AIR LxS	Standard version — cost-effective	6–8 years	Standard	General-purpose vehicle fuel monitoring
LIGO AIR LxT	Extended-battery version	8–12 years	Standard	Long maintenance interval applications, harsh environments
LIGO AIR PRO	Long-range version — high TX power	6–8 years	2× Standard	Marine, industrial tanks, metal-obstructed environments

Part Numbers

Part Number	Length L (mm)	Variant
LIGO-AIR-L7S	700 ± 3	Standard
LIGO-AIR-L7T	700 ± 3	Extended battery
LIGO-AIR-PRO-L7S	700 ± 3	Extended range
LIGO-AIR-L10S	1000 ± 3	Standard
LIGO-AIR-L10T	1000 ± 3	Extended battery
LIGO-AIR-PRO-L10S	1000 ± 3	Extended range
LIGO-AIR-L15S	1500 ± 3	Standard
LIGO-AIR-L15T	1500 ± 3	Extended battery
LIGO-AIR-PRO-L15S	1500 ± 3	Extended range

Custom lengths up to 6000 mm available on request.

Ordering

Item	Information
MOQ	10 units
Lead time (standard)	2–4 weeks
Lead time (custom)	6–8 weeks
How to order	contact@sojielectronics.com or authorized distributors
Custom versions	Available — contact sales for specifications

Interface / Connection Overview

LIGO AIR is a wireless-only product with no external electrical connectors. All communication is via Bluetooth Low Energy.

Wireless Interface

Parameter	Specification
Protocol	Bluetooth Low Energy 5.4
Standard	IEEE 802.15.4-2006
Frequency band	2400–2483.5 MHz (2.4 GHz ISM)
TX power (LIGO AIR)	Up to +6 dBm
TX power (LIGO AIR PRO)	Up to +19.5 dBm
Sensitivity	-95 dBm
Modulation	GFSK
Advertising interval	5–10 s (standard), 10–15 s (PRO) — configurable
Antenna type	Directional (integrated)

Mobile App Interface

Configuration and data reading via LIGO BLE Configurator mobile application:

• iOS — App Store
• Android — Google Play

Refer to LIGO Air Configuration for setup details.

Supported Advertising Protocols

Protocol	Status	Use Case
SOJI Protocol	Default	Native SOJI integration
Mielta Protocol	Selectable in app	Mielta telematics platforms
Escort Protocol	Selectable in app	Escort telematics platforms

Technical Specifications

Performance

Parameter	LIGO AIR (LxS, LxT)	LIGO AIR PRO	Unit
Measurement accuracy	± 0.5		%
Resolution	12		bit
Sampling period	5 to 60		s
Measurement interval	5 to 10		s
Advertising interval	5 to 10	10 to 15	s
Temperature measurement error	± 2		°C

Electrical

Parameter	LIGO AIR LxS	LIGO AIR LxT	LIGO AIR PRO	Unit
Battery type	Li-SOCl₂ (Lithium Thionyl Chloride)
Battery voltage	3.6			V
Battery capacity	2600	2400	3600	mAh
Current (working mode)	9	9	27	µA
Current (storage mode)	4			µA
Battery life (expected)	6–8	8–12	6–8	years
Battery replaceable	Yes

Wireless

Parameter	LIGO AIR	LIGO AIR PRO
Bluetooth protocol	Bluetooth Low Energy 5.4
Standard	IEEE 802.15.4-2006
Frequency	2.4 GHz ISM band
TX power max	6 dBm	19.5 dBm
Sensitivity	-95 dBm
Antenna	Directional (integrated)
Range	Standard	2× Standard
Advertising protocols	SOJI (default), Mielta, Escort

Mechanical

Parameter	Value	Unit
Standard probe length (L)	700, 1000, 1500 (up to 6000 custom)	mm
Head dimensions (W × L)	87.1 × 84.6	mm
Head height	31	mm
Probe diameter (outer)	Ø 36	mm
Probe diameter (inner)	Ø 20	mm
Housing material	Heavy-duty metal alloy
Probe material	Stainless steel
Mounting	4 × M5 screws, 70.5 × 70.5 mm spacing
Built-in accessories	Anti-mud oil filter, anti-vibration springs

Environmental

Parameter	Value
Operating temperature	-40 °C to +85 °C
Storage temperature	15 °C to 30 °C, RH < 60 % (long-term)
Humidity (operating)	5 % to 95 % RH non-condensing
Ingress protection	IP69K (dust-tight + high-pressure high-temperature water jets)
Vibration resistance	Per IEC 60068-2-6
Shock resistance	Per IEC 60068-2-27
Service life (expected)	10 years

Memory

Parameter	Value
Memory type	32 Mb EEPROM (built-in)
Data log capacity	90 days continuous storage
Setting log capacity	Max 500 logs

Mechanical Dimensions

LIGO AIR overall dimensions in mm

LIGO AIR overall dimensions (mm)

All dimensions in millimeters (mm). Tolerances: ± 3 mm for length L, ± 0.5 mm for head dimensions, unless otherwise specified.

Length Variants

Part Number	Length L (mm)
LIGO AIR – L7S, L7T, LIGO AIR PRO – L7S	700 ± 3
LIGO AIR – L10S, L10T, LIGO AIR PRO – L10S	1000 ± 3
LIGO AIR – L15S, L15T, LIGO AIR PRO – L15S	1500 ± 3

Mounting Pattern

Mounting hole pattern

Mounting hole pattern

Item	Specification
Central hole	Ø 42 mm (for probe)
Mounting holes	4 × Ø 7 mm
Mounting hole spacing	70.5 × 70.5 mm
Recommended fastener (≤3 mm wall)	M5 rivet nut
Recommended fastener (>3 mm wall)	M4.8 self-tapping screw

Compliance and Certifications

Wireless / Radio

Region	Standard	Status
EU	RED 2014/53/EU, EMC 2014/30/EU	✓ Compliant
US	FCC Part 15.247	✓ Compliant
Canada	ISED RSS-247, RSS-Gen, ICES-003	✓ Compliant
UK	UKCA, UK RED	✓ Compliant
Japan	MIC (Telec)	(pending)

Environmental

Standard	Status
RoHS 3 (2011/65/EU + 2015/863)	✓ Compliant
REACH (EC 1907/2006)	✓ Compliant
WEEE (2012/19/EU)	✓ Registered
Battery WEEE (2006/66/EC)	✓ Registered (Li-SOCl₂ battery)

Mechanical / Safety

Standard	Rating
IEC 60529 (Ingress Protection)	IP69K
IEC 60068-2-6 (Vibration)	Compliant
IEC 60068-2-27 (Mechanical shock)	Compliant
UN 38.3 (Battery transportation)	✓ Compliant

Industry-Specific

Membership / Standard	Status
Bluetooth SIG	✓ Adopter Member
Bluetooth Qualification	✓ Qualified — see LIGO Air Memberships

Warranty

• Warranty period: 3 years from date of shipment
• NOT covered: Battery
• Warranty void if: Operating conditions exceed specifications, unauthorized modification, or improper installation

For detailed certification documents and approval IDs, see LIGO Air Certification & Approvals.

Related Documents

Document	Version	Description	Download
LIGO Air User Guide	1.2	Installation, configuration, operation, troubleshooting, maintenance	📄 PDF
LIGO Air Configuration	—	Mobile app setup, calibration, BLE protocol integration	—
LIGO AIR Protocol Integration	1.1	Detailed BLE advertising format and payload data structure	📄 PDF
LIGO Air Certification & Approvals	—	Regulatory approval IDs and compliance details	—
LIGO Air Memberships	—	Bluetooth SIG, WEEE registrations, and industry memberships	—
LIGO Air Nomenclature, classification codes	—	HS codes, ECCN, customs classification	—
LIGO BLE Configurator App User Guide	—	Mobile app installation and usage	(coming soon)

Revision History

Date	Version	Description
18/06/2025	1.0	Initial release
14/07/2025	1.0.3	Minor corrections to specifications
14/10/2025	1.1	Added LIGO AIR PRO variant and extended battery variants (LxT)

---

© 2025 SOJI Electronics JSC. All Rights Reserved. Specifications subject to change without notice. Contact SOJI Electronics for the latest information.